First, scientists announced the invention of 1.5 million-year-old footprints, which prove that two different pre-human species coexisted in Kenya. The traces indicate that species could have interacted, raising latest questions on the behavior of our ancestors.
“I would expect that these two species would be aware of each other’s existence in this landscape and would probably recognize each other as ‘different’.” Kevin Hatalaa paleoanthropologist at Chatham University in Pennsylvania, told Live Science in an email.
Hatala led a team of researchers that analyzed footprints that were discovered in 2021 on the Koobi Fora site on the eastern shore of Lake Turkana. The researchers published their findings on Thursday (November 28) within the journal Science.
Many fossil traces have been discovered in East Africa, e.g famous track in Laetoli, Tanzania, made by Lucy species 3.6 million years ago. However, researchers noticed something unique concerning the Koobi Fora track: two bipedal animals with significantly different feet created tracks along the lake shore hours apart.
Several species of hominins, including two sorts of Australopithecines and 4 representatives of the genus, have settled on the Koobi Forums over the course of roughly 3 million years. However, since the fossil record is incomplete and fragmentary, paleoanthropologists have been unable to find out which hominins lived in the identical landscape at the identical time.
Related: New research suggests ancient human ancestor Lucy wasn’t alone – she lived alongside at the least 4 other species of proto-humans
The newly discovered Koobi Fora footprint trail is roughly 8 meters long and consists of 1 track consisting of a dozen tracks made by one person and three more tracks made by other people. The giant extinct marabou stork () also stalked the wet mud, which was quickly buried and preserved.
Hatala and colleagues used 3D imaging techniques to evaluate the form and movement of the track creator’s feet. They found that two of the isolated footprints had high arches and a heel-to-toe foot, much like modern humans. These traces were probably left by our direct ancestor, who had a body shape and size very much like humans.
However, a trail of a dozen tracks revealed a different pattern. These tracks were much flatter, with a deeper forefoot strike in comparison with the heel strike. The researchers also noted that the large toe was barely spread apart and never fully in line with the foot as is the case in humans, suggesting that the track maker likely a strongly built Australopithecus with large jaws and a divergent big toe.
The sizes of the feet varied, but researchers do not need enough information to find out whether the footprints were made by men, women or children, Hatala said. He added that a dozen or so marks were left by someone who would have worn American men’s size 8.5 or women’s size 10 shoes, while individual marks were smaller, roughly a size 4 for girls and a men’s size 6.
Zach ThrockmortonA paleoanthropologist at Colorado State University who was not involved within the study told Live Science in an email that “Hatala and colleagues’ footprint comparisons provide compelling evidence for the coexistence of Koobi Fora in and on Kenya for approximately 1.5 million years . ago.” The stability of the large toe is essential to a person’s ability to walk and run without foot problems, Throckmorton said, and “less the modern, human-like track is credited with lacking this critical adaptation.”
In addition to revealing necessary anatomical differences, footprints reveal the behavior of our hominin ancestors.
“Traces are a snapshot of a moment” Jeremy DeSilvaa paleoanthropologist at Dartmouth College who was not involved within the study told Live Science in an email. The latest research means that “we now know with certainty that these two different types of hominins not only lived at the same time, but shared the same landscape and moved with slightly different steps,” DeSilva said. “I wonder what they thought of each other and how they interacted with each other, if they interacted at all.”
Hatala said the interaction between chimpanzees and gorillas may resemble this interaction – two species that were observed during each positive AND negative social interactions. But the newly discovered marks were discovered inside a few feet of one another, made in a short time, and could have been closer than we ever thought.
“It’s fascinating to think about what they would think when they saw each other and how they would react to each other,” Hatala said.
